KELT-2Ab is an extrasolar planet that orbits the star KELT-2A approximately 440 light-years away in the constellation of Auriga.[1] It was discovered by the KELT-North survey via the transit method - so both its mass and radius are known quite precisely - in a paper led by Thomas Beatty. As of its discovery KELT-2Ab is the fifth-brightest transiting Hot Jupiter known that has a well constrained mass. This makes the KELT-2A system a promising target for future space- and ground-based follow-up observations to learn about the planet's atmosphere.[3]

KELT-2Ab
Discovery
Discovered byKELT-North
Discovery date7 June 2012
Transit
Orbital characteristics
0.5504 ± 0.00086 AU (82,339,000 ± 129,000 km)
Eccentricity0
4.1137913 ± 0.00001 d
Inclination88.56 ± 1.14
2455974.60338 ± 0.00083
90
Semi-amplitude161.1 ± 7.8
StarKELT-2A
Physical characteristics
1.290 ± 0.057[1] RJ
Mass1.524 ± 0.088[1] MJ
Mean density
0.940 ± 0.090 g/cm3[1]
22.7 m/s2 (74 ft/s2)
2.3 g
Temperature1994±104 K or 1782±111 K[2]

The water vapour was detected in planetary atmosphere in 2018.[4]

The star KELT-2A is a member of the common-proper-motion binary star system KELT-2 (HD 42176). KELT-2B is an early K dwarf approximately 295 astronomical units away.

See also

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References

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  1. ^ a b c d Beatty, Thomas G.; et al. (2012). "KELT-2Ab: A Hot Jupiter Transiting the Bright (V = 8.77) Primary Star of a Binary System". The Astrophysical Journal Letters. 756 (2). L39. arXiv:1206.1592. Bibcode:2012ApJ...756L..39B. doi:10.1088/2041-8205/756/2/L39. hdl:1969.1/178896. S2CID 14271501.
  2. ^ Garhart, Emily; Deming, Drake; Mandell, Avi; Knutson, Heather A.; Wallack, Nicole; Burrows, Adam; Fortney, Jonathan J.; Hood, Callie; Seay, Christopher; Sing, David K.; Benneke, Björn; Fraine, Jonathan D.; Kataria, Tiffany; Lewis, Nikole; Madhusudhan, Nikku; McCullough, Peter; Stevenson, Kevin B.; Wakeford, Hannah (2019), "Statistical Characterization of Hot Jupiter Atmospheres Using Spitzer's Secondary Eclipses", The Astronomical Journal, 159 (4): 137, arXiv:1901.07040, Bibcode:2020AJ....159..137G, doi:10.3847/1538-3881/ab6cff, S2CID 119209434
  3. ^ The MgI line: a new probe of the atmospheres of evaporating exoplanets
  4. ^ Piskorz, Danielle; Buzard, Cam; Line, Michael R.; Knutson, Heather A.; Benneke, Björn; Crockett, Nathan R.; Lockwood, Alexandra C.; Blake, Geoffrey A.; Barman, Travis S.; Bender, Chad F.; Deming, Drake; Johnson, John A. (2018), "Ground- and Space-based Detection of the Thermal Emission Spectrum of the Transiting Hot Jupiter KELT-2Ab", The Astronomical Journal, 156 (3): 133, arXiv:1809.05615, Bibcode:2018AJ....156..133P, doi:10.3847/1538-3881/aad781, S2CID 119033501
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